A nurse is providing teaching to the parents of a newborn about newborn genetic screening. Which of the following statements should the nurse include in the teaching?

Rationale: A. Newborn genetic screening is not performed using venipuncture from the antecubital (inner elbow) area. Newborns have very small veins, and venipuncture in this area is invasive and unnecessary for routine screening. Instead, a heel stick is used because it provides an adequate capillary blood sample safely and with minimal tissue damage. The lateral or medial heel is the preferred site because it has a good blood supply and reduces the risk of injury to underlying structures such as bone. B. Newborn screening is a blood test and does not require any oral intake preparation. Giving water to a newborn is inappropriate and potentially unsafe, especially in the early neonatal period where exclusive breastfeeding or formula feeding is recommended. The accuracy of the test is not influenced by feeding status, so no pre-procedure hydration or fasting is needed. C. Newborn genetic screening is optimally performed after 24 hours of life because many metabolic substances and physiological processes stabilize after birth. If testing is done too early (for example, within the first 12–24 hours), results may be inaccurate, particularly for metabolic and endocrine disorders such as phenylketonuria (PKU) or congenital hypothyroidism. Waiting at least 24 hours allows the newborn to have ingested protein and begun metabolic processing, which improves the reliability and sensitivity of the screening. Ideally, it is also done before hospital discharge so that early detection and intervention can occur if abnormalities are found. D. Routine newborn screening is generally a one-time test performed shortly after birth. It is not automatically repeated at 2 months of age. Repeat testing may only be required if the initial sample was collected too early, was inadequate, or if results are abnormal or inconclusive. Otherwise, no scheduled repeat screening is required as part of standard newborn care.